David Mason is a British boulderer who's climbed up to V13/14 (King of Limbs in South Africa) and many boulders between V10 and V13. In 2014, he managed to send 20 boulder problems between V11 and V13 during a 17-day trip to Vastervik, Sweden. He's a Senior Coach at The Climbing Works, a gym in Sheffield, England, and he does personal training/coaching for people there. He's known for his relentless training, and that's what we talked about in this interview. 

• Dealing with failure

• Video of David Mason on King of Limbs

• Check out our Route Climbing Training Program for route climbers of all abilities.